644428628202 has 32 divisors (see below), whose sum is σ = 1293833217600. Its totient is φ = 213980444928.

The previous prime is 644428628183. The next prime is 644428628203. The reversal of 644428628202 is 202826824446.

It is not an unprimeable number, because it can be changed into a prime (644428628203) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13176498 + ... + 13225314.

It is an arithmetic number, because the mean of its divisors is an integer number (40432288050).

Almost surely, 2^644428628202 is an apocalyptic number.

644428628202 is an abundant number, since it is smaller than the sum of its proper divisors (649404589398).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644428628202 is a wasteful number, since it uses less digits than its factorization.

644428628202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57270.

The product of its (nonzero) digits is 2359296, while the sum is 48.

The spelling of 644428628202 in words is "six hundred forty-four billion, four hundred twenty-eight million, six hundred twenty-eight thousand, two hundred two".